1. Field of the Invention
This invention relates to an apparatus which is adapted to be towed behind a vehicle and which operates to form cross country skiing tracks in a snow covered surface.
2. Description of the Prior Art
In the conventional apparatus of the above-mentioned type, a trailer frame is connected to the vehicle in a manner which prevents the frame from pivoting in a horizontal plane. The frame carries a blade and a ski track device. The blade also is fixed against movement relative to the frame in a horizontal plane, whereas the ski track device is connected in a manner which allows it to pivot freely in a horizontal plane. In order to make it possible for the ski track device to adapt to the terrain and to compensate for the steering movements of the vehicle, the ski track device is positioned at a considerable distance behind the blade. A control mechanism is connected between the frame and the vehicle. The control mechanism operates to vertically pivot the frame between a lowered operative position at which the blade and ski track device are in contact with the snow covered surface, and a raised inoperative position at which the blade and ski track device are clear of the snow covered surface. This type of apparatus has proved itself in practice. However, it has turned out that it would be beneficial to improve on the ability of the apparatus to follow the steering motion of the vehicle from which it is being towed.